Telephone repeater system.



No. 894,170: PATENTED JULY 21, 1908.

N. G. W'ARTH. TELEPHONE RBPBATER SYSTEM.-

APPLIOATION FILED APR. 22, 1907.

anmmtoz 9 Y NATHANIEL G-.WARTH 5 Main/w UNITED STATES.

NATHANTEL G. WARTH, orcoiiUMBUs, 01110;.

TELEPHONE REPEATER- SYSTEM.

To all whom it may concern: v

Be it known that I, NATHANIEL G. WARTH,

" a citizen of the United States, residing-at l peater, Systems, of which the following is a Columbus, in the county of Franklin and State of Ohio, have invented a certain new and useful Improvement in Telephone Re&

2 specification.

This invention was briginally disclosed in my'application filed April 23, 1906, pursuant .to which my Patent No. 845,282, dated February 26, 1907, was issued and is divisional with Preference to said application.

The present invention relates more articularly to the repeater circuits and t e repeater or relay apparatus at fa repeater station} and generally stated, one object of my -such inward currents.

invention is to provide a reciprocally operativegrepeater apparatus operating without the use 50f switches ,forchanging the circuit arrangement for the transmission 1n the recipfor fa double or system in which each of the twd repeater instruments receives the weakened initial currents from its respective line or circuit, reproduces the currents with.

exactness and augmented volume, and re transmits them into the associated line cir- 'c'uit, with the. full effect of the transmitter Each of the two transmitters thus sending its whole current into the line circuit assigned it and without division of the current between the two circuits connected. 1 Such division takes place in the system nlow in commercial use and resultsin inferior transmission.

' A further ob'ect of myinvention is to establish for eac of the repeaters associated local circuits by providing'diiferential' orneutralizing action upon eachfrepeat'er-receiver to the locally set up I currents. This local balance is not disturbed or.upset by the inductively received initial line currents in either receiver element, yet eachreceiver element is rendered sensitive and responsive to These constant electrical balances'are maintained by inductively operating ,the repeater-receiver element of 4 Specification of Letters Patent. Original application filed April 23, 19 06,'Seria1 313,192. Divided and this i Serial No. 369,524.

Patented July 21, 190s. pplication filed April 22, 1907;

each repeater by means of translating devices with the line circuit sections. Thus, any un-' balanced condition, whether nor al or'accidental, in either line circuit sedtion, o an unbalanced state of onesction'with rela tiod to the other, will not upset the local balance a established. Were it not for this balance ,local or self-action, producing a .howling or singing noise, would be created by the apparatus, and were the balance not mainliamed in an independent manner by bothrepeater receiver circuits being physically separated from' the line. circuits, yet operatively' associated therewith by inductive means, such interfering self-action would be "gset up whenever the balance in the line circuits {is materially disturbed. 1 All metallic telethe other repeater systems nowin commercial I 5 service the line sections must also he care rocal directions, and also consists in GlICllltS fully and individually balanced, as circuits, on each side of the repeater apparatus. The other systems require for such special balancing adjustable resistances and capacities in the circuits, or-derived or artificial balancing circuits and artificial lines, etcL, each ofwhich methods dissi ates the transmitted currents and'serious y reduces-the volume and efficiency of the transmission.

The figure illustrated herewith is one em bodiment of my invention'and will be readily understood from the following description.

The fi tire is a diagram; representing two electricafiy widely separatedtelephone stations with their respective line circuits terminating' at an intermediate point at a ,repeate'r station in a double or twin reciprophone circuits are electrically balanced, each 5 wire with its mate-,for normal operation, and in cally operative telephone repeater instruable resistance "transmitter -allabeing "associated in repeater relation, and the two repeaterunits being electrically associated in reci rocally transmitting repeater relation. Bot units, together with their local circuits,

line translating devices or induction coils are inductively associated withtheir res ective line circuits through the'medium of 't eir respective secondary windings of the induction p local batteries and their local windings of the as a secondary, according to coils connected therein. .I-Ierein the terms primary or local and secondary with reference to the windings of the line induction coils are not material, as each winding is alternately used as a primary or the trend or direction of the transmission. g

The drawing herewith illustrates a twin or double. repeater arrangement comprising two sets of a paratus, R and R ,'with neutralizlug-win ings, N and N respectively incororated on each receiver core but connected m'the local circuitof the opposite receiver. The two principal windings N and N of these recelvers are-so disposed as to. actuate -each:"receiver transmltter by currents from 'either line induction coil 0 or 0 when the letter are caused to transform currents from the line circuits L and L, and these said neutralizing windings, together with windings N and Nfi also operate to neutralize or prevent magnetic" action in the receivers from currents fiowin through them from the transmitter local atteries B and B In this aparatus the receiver coils are shown included m the primary or transmitter local circuits for the purpose of reducing the a paratus,

- circuits and line induction coil win 'ngs to a minimum, and avoiding current losses in unnecessary windings and conversions. The re-transmission is effected in both directions, as both repeaters act in unison, but the transmission is in but one direction from each instrument. 'Full transmitting efficiency is thus secured in one direction 'from each transmitter. There 1s a practical se aration of the two'sections of the compoun circuit from direct inductional or transmission effects into each other, as the low converting efficiency of the low wound receivers is practical-ly negligible for such transmission. This arran ement affords no opportunity for interfenn local action a inthe repeaters to cause owling as the receiver coils are dif ferentiallyconnected and neutral to the primary eflfects, and the line conditions if un- "balanc'ed cannot affect the receiver circuits 7, to unbalance them, as the line induction line current setup at the terminal telephone,

" coils C and C conductively se arate the -re- ,ceiver circuits proper from the e circuits so that transformin currents only'can affect the repeaters.

he broken arrows'm view conventionally indicate a transforming S and the solid arrows indicate the local currents primarily caused to flow by the action upon the cores of the receivers by the transformed or induced line current. A reversal of transmission produces like effects in the opposite direction without switches for chang-' ing thecircuit arrangement, as in some repeater systems. 1

To adapt the circuit to composite or through signaling service the two sections L and L of t e'compound circuit are connected Tizing windings N together around the repeater apparatus by the conductors A and lnwhich suitable 'reactance or' choke coils F and F are in cluded. I The condensers J, J", etc., are required when the composite or signaling service is separately operated on the two wires vof the metallic circuitin a well-known way.

Other composite orsignalin apparatus and circuit conditions are not il ustrated or explained as they are well-known and this inthrough transmitter M of repeater R, which latter is more particularly associated with line circuit section L. The consequent actu': ation of transmitter M, which is actuated by winding N, setsup from local battery B a repeatingcurrent which is a duplicate of that set up inthe first mentioned associated local circuit by transmitter M and battery B These duplicate primary currents are balanced in both receivers through theneutraland N acting differentially to windings N and N respectivelyon the reand N of the repeaters, see broken arrows 'next local circuit) thence joining flows ceivers and operate to neutralize the recelvers and create an Inert state thereof and of the transmitters to the locally produced currents, thus reventing local action of the apparatus an avoiding the .noise termed singin or howling., 'It will be observed t at these double or twin local circuits have only an'inductive operative relation to the line circuit sections, thereby insuring the continuance of the balances set forth regardless of variations of balances in the line circuits. The duplicate current (see the solid arrows) set up battery'B flows through the then. primary in thelocal circuit by winding of. re eatin coil-0, thence through 1 princi al'win ing and.neutralizing windmg z of the repeater-receivers, thence through transmitter M of repeater R,

tvhichlatter is more particularly associated with line circuit s'ectionL, thence returning I to the battery. Similar'actions and effects are simultaneously setup in the first mentioned local circuitb transmitter M and battery B by the act on of princi a1 wind-1 mg N 4 and neutralizing winding Hence both receivers are rendered. neutral and inert to the locally'set up and reproduced currents. The currentsthus set up by;

transmitter ;M are induced into line circuit section L b' the'induction .coil C and are transmitted thence to the terminal station" telephone S, thereby'completing thecycleof- 'initlal' transnnssion, repetition, and retrans mission, It will be nnderstood'that there ciprocal of these current-flows,- and effects occurs with each change in the directionfrof transmission or use of the line. 5 For the establishment of=an initial mag .netic-field in the receivers of the re eaters R and R? for their sensitization I pre er to, emplejy-for each 'a permanent magnet.

he system may beoperated in connection with superposed circuits and their currents,- and also with a flexible cord circuit and other desired auxiliary apparatus. Modifications of this inverition'as illustrated herein may be-made Without-departingfrom. the'substano'e of it.

. What I claim-and desire "to ters Patent is: F, v r.

1.' In a relay for telephone-lines, two induction-coils, two transmitting devices,'mag-- 25 netically-controlled'"means o erativelycon- I nected therewith, andtwo in eperident-eleC tro-magnetic means includedl'in closed local circuits solely with the secondaries'ofsaid induction-coilsm- 3 2. In "a reci rocal telephone repeating system, the combination with telephone-line sections, of repeating -relays, each induct-' ively responsive to currents originated" in its respective line-section and unresponsive to currents produced by it in the other linesection", as set forth. '3. In a telephone repeater system, the combination with a main line circuit, of two sets of receiver transmitter-repeaters in local 'secure V 40 circuits associated with said main line induct- -ively, and meansffor balancing said receivers in-the'local circuits against local self-action and reproduced line currents. 4. In a telephone repeater ap aratus, local circuits, two repeaters in inductive local 'rela tion'toa line,'local balances for the repeaters producing a differential fiowof local currents I for controlling the re eaters to' render them inoperative or inert, to said locally produced currents. r v i 5. In an automatic reciprocal telephone repeating system, the combination of a main te ephone clrcurt divided into independent sections, two re eaters, differential windings in balanced re ati'on to the reproduced or locally set up currents, circuit means for rendering the repeaters responsive to the originating line currents, local circuits for the repeaters inductively associatedwith the main circuit, current supply for the repeaters for renewing the origmating line currents with increased power, each repeater transmitter operating to induce its reproduced current in one line section. v a

other; means for -associating'fbo and gboth transmitters wit '7.' In a deuble telephone repeaterftwo .repeater relation.

local circuits, each repeater beingparticularly rents produced by itinthe 0t er linecircuit, 'current supply for the repeater-transmitters,

6. In a double or twin telephone repeater self action in the repeaters is prevented;

apparatus, localcircuits each embracing a current supply :and. a receiyer trans-v mitter associatedin repeater rela 11 each a rvely,-:;electrical balances in thestwin "local circuits for each repeater forpreven tinglocal self-action therein,- the sa d indnc'ive asso-.

ciating means*render' g the said balances,

self-dependent and -'constant..' i ,75'.

primary er local-circuits eachembracing in combination a primary or local winding of an tion il, a source of current sup 1y,"

and a receiver and transmitter associate -u1 8. a telephone repeater, the combinatlOlLOf two rece vers having neutralizing differential windings and two transmitters me chanically and electrically associated with sardreceivers in re eater relation, two local circuits each inclu ing'awinding of each receiver for balancing it againstlocal self ac-' tion, a transm tter, a current supply and means for associating both repeaters with a an 'linez inductively, whereby the said balance against local action is made constant, In a telephone" repeater system, the

combination of two line circuits having tele' phones, two local or primary-circuits, one for each line'circuit, repeating or'induction coils inductively uniting said line circuits to their a respective local circuits, two independent or separate telephone repeaters connected in said associated with'its respective line circuit so that its transmitter operates through its particular local circuit and'coil to induce'its en- 5 tire retransmitting current into that line circuit, current supply for the repeater-transmitters, associated divided windings for the repeater-receivers and a circuit arrangement and electrical balances whereby local or self action in therepeaters 1s prevented.

10. In a telephonev repeater system, thecombination of two line circuits having telephones,. two local or primary circuits one for each line circuit,-repeating or inductio'ncoils inductively uniting said line circuits to their respective local circuits, two independent or separate telephone repeaters connectedjm sald local circuits, each repeater being articularly associated with-its respective inecircuit so that its transmitter operates through its particular local circuit and coil to induce its retransmitting current into that line circuit,each repeater being inductively responsive. to currents originated in its respectlvellne circuit and unres onsive to ourdivided windings for therepeater receivers and an associated circurt means whereby electrical balances are malnt'alned and local or 11.",In aftelephonic repeater system, .the

combination of induction coils, two telephone lines or line sections, a repeater apparatus joining said lines or line sections, said repeater apparatus ,consisting'of twin units within -twin local circuits and operating simu-ltaneously, each receiver having two tern, alrepeating said apparatus embracing two independent units, each unit comprising a'recelver and a transmitter associated in repeater relation,

transmitters.

windings, one of which is in circuit with its twin. receiver, each receiver actuating its transmitter which is connected in the other Side or opposite of the twin circults, .to transmit in that one direction, the twin local cir- "cuits 'working inductively with the line, the

incoming or received currents energizing-the receivers and actuating the transmitters, the retransmittingcurrents being made to flow differentially through the receiver windings and,-.thereby prevent local action upon the :In a reciprocal telephone repeater sysapparatus at an lntermediate station on a me circuit connected through said repeating apparatus for repeater service,

the units being electrically associated in repeater relation and being in inductive relarepro tion to the line circuit, and associated local circuit means whereby the repeaters are con stantl maintained unresponsive to their d uced and locally set-up currents but are res onsive to the initial line currents.

13. n a telephone repeater system, the combination of two main telephone circuits ortwo, sections of a circuit, two repeater units, two induction coils, one for each main circuit, associated local repeater circuits each inductively connected with its respective main circuit or circu t section, each repeaterreceiver and one repeater-transmitter $188001 ated with each local circuit including a current supply, means for rendering the repeaters insensitive to the locally set up and retransmitted currents, each of said.- induction coils constituting a common medium for re ceiving from and sending to their respective main circuits the inward and the reinforced outward currents. a

14. In a telephone repeating system, the

. combination of two main line circuits extending from outlying telephone stations and Y joinedat a repeating station by a double tele-.

phone repeater, local repeating circuits for the repeaters, induction coils uniting said local circuits to their main line circuits rev the local currents and the induced line circuitspectively, the-receiver magnets each having" two windings, one winding being in each of the local re eating circuits together with the battery and the transmitter for that circuit, the battery currents energizing the receiver windings differentially to roduce inaction to currents operating the receivers and actuating their transmitters, there-transmitting but one direction.

currents set u bein induced into the line circuits throug the induction coil windings uniting the local repeating circuits to their respective-main line line circuits.

1 15. Ina reciprocal telephone repeater sys- 0 tern, a main line .ci'rcuit, two cooperating telehone repeaters at a'repeajter station on said 111e, local circuits'ifor the repeaters and a source of current supply therein,said.local circuits bein inductively assbciated with the line circuit, ifferential windings in said local circuits for balancing the current effects for" 'the repeaters to render the same unresponyet sensition of two receivers and two transmitters associated together in repeater relation,

local circuits therefor, a current supply-for 1 the transmitters, each receiver having difler-- ential windings in the local circuits in electrically balanced arrangement, and also having its transmitter connected to transmit in.

18. In a telephone repeaters stem, two

repeaters, a sectionally divided 'ne circuit,

the line and local circuits, local current supply, two differential windings in the local circuits controlling the receiverelements to render the same inert to the reproduced cur- 65 rents but active to the initially received line currents, the transmitter elements being arranged to transmitinto but one line section.

19. In a telephone repeater system, the

combination of a main circuit formed of two 1 circuits or two circuit sections associated for repeater servlce, two repeaters, each com-" pr slng receiving and transmitting mediums, I

induction coil windings operatively associating all said repeater 'mediums inductively 11.5

with said main circuit, each receiver actuat- 'ing itsrepeater transmitter and each transmitter re eatinginto a difierent circuit sectlon, eac receiver being rendered inert by differential windings to the local or repro- 12c (duced currents flowing in the difierential windings but sensitive to the initial inward currents flowing through said windings nondifferentially.

20. In a telephone repeater apparatus, the 12.5

combination of two repeaters, local circuits therefor, said local circuits being divided and containing induction coil windings in inductive relation to a line circuit and connected up or arranged to cause locally produced 1;)

- g I I O local circuits, inductive WIIIdIIIgSflSSOCIatIIIg cluding the primary or local division of the induction COll windings,local battery or current supply for retransmitting, two repeating telephones, and differential windings therefor included in the local circuits and being in inductive relation to the line circuit, the re- .ceivers of the repeater being controlled by individuall established electrical balances in the loca circuits, each balance including a differential winding and the arrangement adapted to produce neutral effects by the locally set up currents uponthe receivers, each receiver being actuated by initial line currents from one line section to individually actuate its respective transmitter to vary its battery. current and transmit renewed or repeated duplicate currents into the associated or opposite line section only, whereby reciprocal re-transmission is obtainable and without reactive interfering local self-action in the" apparatus or reaction by the re roduced' currents, and wherein the local alances are constantly maintained regardless of absence of balance in the main line circuit.

22. In a telephone repeater, two repeaters, two divided local circuits by which the re peaters are controlled, each re eater having a local differential current-ha ance to prevent interferin reaction.

23. In a te ephone repeater apparatus, two repeaters reciprocally cooperatlve, two divided local circuits, one for each re eater, in which the repeaters are control ed by means of differential local current balances to prevent interfering reaction.

NATHANIEL G. VVARTH.

Witnesses:

BENJAMIN FINOKEL, ALICE B. 000K. 

